Malicious PDF — malware analysis report

Static analysis result for SHA-256 04b643499febacb3…

MALICIOUS

PDF

82.5 KB Created: 2021-09-20 16:02:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 77c83196f9f05f500be54e96e028c7a4 SHA-1: 88a3c4efb445ac70055ac5bb33e1a6080eaf4a44 SHA-256: 04b643499febacb345d2b60c465a82a72eeb6329433bbede3440f6558d3021e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm with numerous URLs pointing to disposable hosting, a common tactic for phishing or distributing malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple compromised CMS upload links further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://archism.ru/uplcv?utm_term=3+letter+words+beginning+with+s PDF link annotation
    • http://thuephotocopytaihanoi.com/upload/files/rajipulaxenobilegafonexad.pdfIn PDF document text
    • https://airbays.com/userfiles/file/30796304459.pdfIn PDF document text
    • https://zzwgjx.com/d/files/41965875751.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/f8327cf2cc77ac01d99f8d62a2f0be50/puzanesed.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/21091338320.pdfIn PDF document text
    • https://discovery99.com/userfiles/file/wovaduravewes.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/11281237401.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/89396901253.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/57914094912.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/zuxozajofaxanovosebe.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/najizezaxilo.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/febin.pdfIn PDF document text
    • http://avvolodin.ru/upload/file/62800463688.pdfIn PDF document text
    • https://hanomanberjaya.com/contents/files/52693248055.pdfIn PDF document text
    • https://zlato-stribro-investice.com/upload/files/masatareke.pdfIn PDF document text
    • https://legacytwirlers.cornerfamily.com/userfiles/files/38954655255.pdfIn PDF document text
    • http://firmen-bekleidung.at/userfiles/file/68140267657.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f15163f641---fibuligafugokigojusiwi.pdfIn PDF document text
    • https://quimicasorocolor.com.ve/ckfinder/userfiles/files/33477807407.pdfIn PDF document text
    • https://homestayhoian.vn/uploads/image/files/43275637243.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/0634bdaa412e02dbc614720f288bc930/26816257178.pdfIn PDF document text
    • http://aaz.sk/editor_uploads/files/bozolasiwetegozeju.pdfIn PDF document text
    • http://fedime.org/imagenes/14666803785.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/bixezuvokamotizij.pdfIn PDF document text
    • https://artistprasanna.com/userfiles/file/bevukosogefoxeza.pdfIn PDF document text
    • http://productinfo.in/konadnew/userfiles/file/70212709766.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB25 10668 bytes
SHA-256: 8f584c133c3a09437b5e44dcd6eb322f6148eebdf9ff8c97f9ee896e41b05d84
font_01_sfnt_off0000f355.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF355 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B67 19072 bytes
SHA-256: 9d7f3b776df967774c68f7809c27a2302708ad120544141f0988f50cc9c0ab4e